Chem 220a                                          Problem Set 1                         Due Sept 15, 2003

 

 

 

  1. Draw Lewis structures  for the following molecules.

E.g., 

 

   

 

 

(a) methylamine, H3CNH2

 

(b) acetamide, H3CCONH2

 

(c) methyl azide, H3CNNN

 

 

 

2. Draw the principal resonance structures for:


(a) acetamide

 

(b) methyl azide

 

(c) pentadienyl cation, CH2=CH-CH=CH-CH2+

 

 

 

3. Identify the hybridization for the non-hydrogen atoms in:

 

(a)    acetamide

 

(b)   capillin (Wade, p. 370)

 

 

 

 

 

 

4. Order the following compounds by increasing boiling point.

 

            CH3CH2CH2CH2CH3                          (CH3)4C

 

CH3CH2CH2CH2NH2                          (CH3)2NCH2CH3 

           

CH3CH2CH2CH2OH

 

 

 

 

5. Order the following compounds by increasing dipole moment.

 

            CF4                                                      (CH3)3CH

           

(CH3)2CO                                            (CF3)2CO

 

 

6.      Order the following compounds by decreasing acidity (increasing pKa).

 

CH3COOH                                          CF3COOH

 

CH3CH2NH3+                                      CH3CH2OH

 

CH3CH2NH2   

 

7.      Identify the functional groups that contain hetereoatoms in:

 

 

 

                                                               

 

            aspirin                                                              phenacetin